Telephone-receiver.



H WIEB. TELEPHONE RECEIVER.

APPLICATION FI'LED OCT. 28. 1913.

Patented Aug. 3,1915.

/n vena/1' Harry 5. VI//ef Ta simens PA- HARRY IB. WIER, 0F PLAINFIELD, NEW JERSEY, A.ASSIGl-NOB. T0 WESTERN ELECTRIC COMPANY, 0F NEW YORK, N. Y., A COBIEUBATION QF ILLINOIS.

TELEPHONE-RECEIVER.

v Specicationof Letters Patent.

Patented. Aug, a, i915.

Application led October 28, 1913. Serial No. 797,759.

To all 'whom it may concern: A

Be it known that I, HARRY B. Wren, a subject of the King of England, residing at Plainfield, in the county of Union and State of New Jersey, have invented a certain new and useful improvement in Telephone-Receivers, of which the following is a full, clear, concise, and exact description.

This invention relates to telephone receivers, and more particularly to receivers for use with wireless telephone and telegraph circuits, and its objects are to provide a structure which will withstand the hard and rough usage obtaining in this class of service, to provide means for readily adjusting the air gap between the magnet and diaphragm and for maintaining said adjustment and, in general, to simplify and improve their mechanical construction.

In accordance with the features of the invention, there is provided a metal casing having adjustably mounted therein, a mem ber carrying the pole-piece and magnet system of a receiver, the position of which, with respect to the diaphragmcarried by said metal casing, may be readily adjusted and locked while the Vreceiver is in position on the operators head.

This invention will be more fully understood by reference to the accompanying drawings, illustrating one embodiment of this invention, and wherein- Figure 1 is a view in perspective of a receiver embodying this invention; Fig. 2 is a view in section on line 2-2 of Fig. 3, and Fig. 3 is a view in section on line 3-3 of Fig. 2.

As shown inthe drawings, the receiver embodying this invention comprisesv a nonmagnetic shell or casing 5, externally i threaded on one end as at 6, and internally threaded on the other end as at 7.

diaphragm 8 of magnetic material ts over one end of the shell 5 and is held in place by a threaded cap 9 of insulating material, engaging the external threaded portion 6 of the shell 5. A plate 10 of non-magnetic material, having the periphery thereof threaded to engage the internally threaded portion 7 of the shell 5, is mounted therein. Mounted upon one side of the plate 10 and extending inside of the shell 5, is a perman-ent magnet 11 which is secured to the Said plate by means of screws 12, 12. Se-

21 extending within the shell 5, are mounted Y upon the outside of the plate l0, one being v insulated therefrom by a washer 22, and the other bemg 1n direct electrical contact with said plate. Each of the` terminals 20 are provided with a screw 23 by means of which.

theconductors of a connecting cord 39 may be connected thereto.

. To provide means for varying the distance between the diaphragm 8 and the ends of the pole-pieces 13, a block 25, having a threaded opening therein, is mounted upon the outside of the plate 5 near the margin thereof. The block 25 is engaged by a thumb-screw 26. An outer casing 27 of brassor other non-magnetic material incloses the shell 5 and is held in place by a bayonet Joint comprising pms 28 in the side of the shell 5, engaging angular slots 29 in the side' of said casing.

The outer casing 27 is provided with a slot 30 through which the thumb-screw 26 passes to engagethe block 25. The thumbscrew 26 is provided with a shoulder 31 which, when said screw is tightened, en.

gages the side of the outer casing 27 adjacent the slot 30 and maintains a definite distance between the ends of the pole-pieces and the diaphragm 8. To adjust the distance between the pole-pieces and the diaphragm, the thumb-screw is loosened; lateral bodily movement then of the screw in either direction will rotate the block 10 and, by reason of the threads thereon which engage the threads in the member 5, will cause a corresponding movement of the pole-pieces either toward or away from the diaphragm. When the desired distance is obtained, the thumb-screw is tightened against the outer casing 27 thereby maintaining said desired distance.

The receiver may besuspended in a headband 35, terminating in an arc 36. Each end of the arc 36 has a pin 37 secured thereto, which engages registering holes 38 in the shell 5 and the Aouter casing 27, thereby supporting'the receiver and preventing movement of the outer casing 27 with respect to the shell 5.

The outer casing 27 may be provided with an opening through which the cord conductors may be brought in to the terminals 20, and there may be mounted in the plate 10 a screw eye 41, to which may be secured the tie cord of the cord 39 to relieve the conductors of any strain.

It will be seen that I have provided a receiver which willwithstand rough and hard usage, and in which the properadjustment of the pole-pieces with respect to the diaphragm, may be readily obtained while an operator has said receiver in operative position on his head, thereby enabling the operator to secure the proper adjustment more promptly than has heretofore been possible. Furthermore, it will be seen that lthe receiver consists of few and simple parts easy to assemble.

I claim:

1. A telephone receiver comprising a cylindrical shell, a diaphragm mounted on one end thereof, a rotatable plate having screw* threaded engagement with the other end of said shell, a magnet mounted upon said plate in operative relation to said diaphragm,`a j

slotted member secured to said shell, a lug secured to said plate, and a screw engaging said lug whereby said magnet may bemoved toward and from said diaphragm and engaging said slotted member to maintain the adjusted position of said magnet.

2. A telephone 4receiver comprising a cylindrical shell, a diaphragm mounted on one end thereof, a rotatable plate having screwplate having said magnet mounted thereon adjustably engaging said casing, a second casing having a slot in the side thereof inclosing said first mentioned casing, a block mounted on said plate, and a screw engaging said block whereby said magnet may be moved toward andfrom said diaphragm, and engaging said second casing to maintain the adjusted position of said magnet.

In witness whereof, I hereunto subscribe ryname this 25th day of October A. D.,

HARRY B. IVIER.

Witnesses:

R. C. HoPGooD, M. V. CoNATY. 

